Genus Biemna Gray, 1867

Diagnosis. Massive, cup­shaped or tubular sponges, with uneven surface. Plumose or plumoreticulate choanosomal skeleton, with variable development of spongin fibres cored by (subtylo­)styles of a single size, occasionally replaced by oxeote spicules; ectosomal skeleton made up of brushes of megascleres making the surface often shaggy; microscleres include sigmas, raphides, microxeas, commata, microstrongyles and spheres. Most species cause a dermatitis­like reaction when in touch with bare skin. About 55 species occur in all oceans (Hajdu & Van Soest, 2002).

bar=100 µm); L. Rhaphides (Scale bar=100 µm).